In biological adhesives and in treating medical devices that are derived from biological compounds, such as porcine cardiac valves, crosslinking agents containing artificially and chemically synthesized aldehydes such as glutaraldehyde or condensing agents such as 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide have been used (for example, refer to patent documents 1 to 6, and non-patent document 1).    Patent document 1: Japanese Unexamined Patent Application Publication No. 7-163650    Patent document 2: Japanese Unexamined Patent Application Publication No. 9-249751    Patent document 3: Japanese Unexamined Patent Application Publication No. 10-71199    Patent document 4: PCT Japanese Translation Patent Publication No. 2000-502380    Patent document 5: Japanese Unexamined Patent Application Publication No. 8-53548    Patent document 6: PCT Japanese Translation Patent Publication No. 8-502082    Non-patent document 1: Biomaterials, vol. 17, p. 765 (1996)